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Forward-backward Minimum Variance Beamforming Combined with Coherence Weighting Applied to Ultrasound Imaging

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Chinese Journal of Biomedical Engineering(English Edition) 2016年第1期25卷 24-30页

作者： ZHOU Ting li qiao-liang CHEN Xin WANG Tian-fu CHEN Si-ping Department of Biomedical Engineering School of MedicineShenzhen University

Currently,the delay-and-sum(DAS) algorithm is used as a standard technique in ultrasound ***,the adaptive ultrasound beamformer shows its superiority over the traditional beamformer,DAS,in many *** this paper,we proposed a novel adaptive beamformer which combined the minimum variance(MV)adaptive beamformer together with coherence weighting factor(CF) and forward-backward averaging(FB) to medical ultrasound *** called it the forward-backward averaging coherence weighting minimum variance(FB-CF-MV) *** on Sonix RP system,we built an ultrasound beamforming research *** used this open platform to collect pre-beamforming RF data,and then processed them in *** tested our algorithm on a fetal ultrasound phantom and compared it with DAS and MV *** results showed that the new beamformer improved image contrast,making the image outline smoother while compared with other two algorithms.

关键词： ultrasound beamforming adaptive imaging

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-Feng qiao Yue-liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Impact of Bubbles on Mechanical Performances in a Borosilicate Glass

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 25-29页

作者： li Chengxing li Dongfeng MA Shilong qiao Ang ZHENG Qingshuang China Helicopter Research and Development Institute Jingdezhen 333001China State Key Laboratory of Silicate Materials for Ar-chitectures Wuhan University of TechnologyWuhan 430070China

To analyze the impact of bubbles on the mechanical behavior of glasses,by controlling the refining time,we prepared three borosilicate glasses with the same composition and different *** the analysis software integrated within the optical microscope,the diameter and number of the bubbles on the surface of three borosilicate glasses were *** the hardness and crack initiation resistance(CR),we built the relationship between the porosity and the mechanical performance of these borosilicate glasses.

关键词： bubbles oxide glass hardness creak initiation resistance

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基于结构相似性的图像质量评价方法

光电工程 2007年第11期34卷 108-113页

作者：朱里李乔亮张婷汪国有华中科技大学图像识别与人工智能研究所生物与医学图像研究室湖北武汉430074

分析现有图像质量评价方法特点,针对基于失真敏感度的质量评价方法的局限性,提出了一种新的基于结构相似度的图像质量评价方法,从亮度、对比度、结构三个子方面得到一个总的相似性度量作为质量客观评价标准。该方法充分考虑了图像的结... 详细信息

分析现有图像质量评价方法特点,针对基于失真敏感度的质量评价方法的局限性,提出了一种新的基于结构相似度的图像质量评价方法,从亮度、对比度、结构三个子方面得到一个总的相似性度量作为质量客观评价标准。该方法充分考虑了图像的结构信息和人类视觉的特性,从图像内容的理解功能出发,通过数学建模估算出人眼对图像质量的主观视觉感受,使结构相似性计算模型符合图像处理应用的本质。通过理论推导和算法验证,该方法可以为选择图像压缩算法和评价图像质量提供依据。将采用压缩算法SPIHT编解码后的图像与传统的峰值信噪比方法评价图像相比,实验表明,本文提出的算法是一种更为有效的图像质量评价方法。

关键词：图像质量评价结构相似性失真敏感度

广义Fibonacci立方体的网络容错性质分析

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高校应用数学学报（A辑） 2007年第4期22卷 491-497页

作者：蒋勉李乔良长沙通信职业技术学院湖南长沙410015 湖南大学计算机与通信学院湖南长沙410082

主要研究广义Fibonacci立方体的容错直径和宽直径,证明了n维Fibonacci立方体网络的k-1容错直径和k宽直径都是n-1,其中k=[n/3].

关键词：广义 Fibonacci立方体容错直径宽直径

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen li Leilei liang Baoshan Zhang Yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei li Qianqian liang li Xu Changsheng Ding Yu liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

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Nano-Micro Letters 2025年第2期17卷 432-446页

作者： Hao Yin Yanting li Zhiying Tian Qichao li Chenhui Jiang Enfu liang Yiping Guo State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Beijing Vacuum Electronics Research Institute Beijing 100015People’s Republic of China Fundamental Science On Vibration Shock and Noise LaboratoryState Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing ***,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also ***,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic *** as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse *** ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate ***,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%*** structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

关键词： Flexible piezoelectric filaments Anisotropic Ultra-high sensitivity Structural health detection Texture recognition

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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Neural Regeneration Research 2025年第8期20卷 2361-2372页

作者： Shengyang Zhou Ting li Wei Zhang Jian Wu Hui Hong Wei Quan Xinyu qiao Chun Cui Chenmeng qiao Weijiang Zhao Yanqin Shen Laboratory of Neurodegenerative and Neuroinjury Diseases Wuxi Medicine SchoolJiangnan UniversityWuxiJiangsu ProvinceChina

Interferon regulatory factor 7 plays a crucial role in the innate immune ***,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains *** we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial *** the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 *** addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and *** together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

关键词： cyclic guanosine monophosphate adenosine monophosphate synthase H151 interferon regulatory factor 7 M1 phenotype neurodegenerative disease neuroinflammation Parkinson’s disease RU521 STING type I interferon